Breaking bad programming habits. What’s yours?

I like to be efficient in my SAS/IML programs, but sometimes I get into bad habits. Recently I realized that I was reshaping a bunch of SAS/IML row vectors because I wanted to write them to a SAS data set.

This is completely unnecessary! The SAS/IML language will create a data set variable from any SAS/IML matrix, not matter what its shape.
For example, suppose that you have a column vector, a row vector, and a matrix, and you want to write their data to a SAS data set, as follows: